1. Field of the Invention
The present invention relates to foldable eyewear, and more particularly to a foldable eyewear design having a spring-hinged connection between a bridge and a lens rim that allows the eyewear to be folded for compact storage.
2. Description of Related Art
Various types of eyewear have been designed to include foldable components that allow a user to store eyewear more compactly. For instance, one known design for glasses, exemplified by embodiments in U.S. Pat. No. 5,896,186 to Huang, has retractable temples and a foldable bridge that allows the user to fold the glasses such that the two lens rims are side-by-side for storage. The benefits of such a design are limited however because the two lens rims are folded side-by-side, thereby resulting in considerable surface area that must be accommodated in the storage container, even when folded.
Another known eyewear design, exemplified by embodiments in U.S. Pat. No. 5,642,177 to Nishioka, provides a detachable sunglass xe2x80x9cfrontxe2x80x9d with a hinged bridge that allows the user to fold the two lens rims of the detachable sunglass front one on top of the other for compact storage. This configuration, however, is prone to unwanted movement of the rims as the hinge loosens after repeated use and does not allow the eyewear to xe2x80x9cgivexe2x80x9d when exposed to force/impact from the front.
The present invention is directed to foldable eyewear having first and second lens rims, a bridge portion between the first and second lens rims, connectors between the bridge and the first and second lens rims, and at least one spring positioned at a folding hinge that rotatably joins the bridge portion and a lens rim-bridge connector. The spring-hinged mechanism that joins the bridge portion and a lens rim-bridge connector allows the user to fold one lens rim on top of the other for compact storage while preventing unwanted instability and transitions between the folded and unfolded positions. The spring-hinged mechanism allows the lens rim-bridge connector to xe2x80x9chyper-extendxe2x80x9d relative to the bridge portion to absorb impact/force without breaking.
According to one embodiment of the present invention, each lens rim-bridge connector includes a forked end portion that fits over and engages with a stepped end portion of the bridge and includes a hollow cavity for housing a spring. The spring in the hollow cavity of each connector is compressed by the force exerted by an edge of the corresponding stepped end portion of the bridge. The force against the bridge exerted by the compressed springs provides stable, yet rotatable, connections between the bridge and the lens rim-bridge connectors. According to another embodiment of the present invention, the bridge includes two forked end portions that respectively fit over and rotatably join with stepped end portions of the lens rim-bridge connectors. At least one forked end portion of the bridge includes a hollow cavity for housing a spring. The spring is compressed by a force exerted by an edge of the stepped end portion of a lens rim-bridge connector. The force against the lens rim-bridge connector exerted by the compressed spring provides a stable, yet rotatable, connection between the bridge and the lens rim-bridge connector.